VALDIR SABBAGA AMATO

(Fonte: Lattes)
Índice h a partir de 2011
10
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Moléstias Infecciosas e Parasitárias, Faculdade de Medicina - Docente
LIM/46 - Laboratório de Parasitologia Médica, Hospital das Clínicas, Faculdade de Medicina - Líder

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Agora exibindo 1 - 10 de 13
  • article 17 Citação(ões) na Scopus
    Case Report: Reactivation of Mucosal and Cutaneous Leishmaniasis in a Renal Transplanted Patient
    (2014) TUON, Felipe F.; BOMBONATTO, Giovana Marina; BATTAGLIN, Eveline Roesler; SAKUMOTO, Marcus Henrique; AMATO, Valdir Sabbaga; CAMARGO, Raphael Abegao de; NICODEMO, Antonio Carlos
    Mucosal leishmaniasis (ML) is a chronic form of tegumentary leishmaniasis, which causes destructive lesions of nasal, pharyngeal, and laryngeal mucosa. We describe a case of leishmaniasis reactivation with simultaneous cutaneous and mucosal forms in a renal transplanted patient with no history of prior leishmaniasis. Reactivation after renal transplantation was not reported in Brazil. A 67-year-old woman receiving prednisone 20 mg/day, tacrolimus 1 mg/day, and mycophenolic acid 360 mg/day presented with nose edema with erythema and cutaneous lesions. Amastigotes were identified on biopsies and the polymerase chain reaction confirmed Leishmania (Viannia) braziliensis. The patient was treated with liposomal amphotericin B but died 3 weeks after as a result of bacterial septic shock. In conclusion, tegumentary leishmaniasis can reactivate with simultaneous cutaneous and mucosal forms in a renal transplanted patient during the immunosuppressant therapy.
  • article 11 Citação(ões) na Scopus
    Facial Structure Alterations and Abnormalities of the Paranasal Sinuses on Multidetector Computed Tomography Scans of Patients with Treated Mucosal Leishmaniasis
    (2014) CAMARGO, Raphael Abegao de; NICODEMO, Antonio C.; SUMI, Daniel Vaccaro; GEBRIM, Eloisa Maria Mello Santiago; TUON, Felipe Francisco; CAMARGO, Lazaro Manoel de; IMAMURA, Rui; AMATO, Valdir Sabbaga
    Background/Objectives: Mucosal leishmaniasis (ML) is a progressive disease that affects cartilage and bone structures of the nose and other upper respiratory tract structures. Complications associated with ML have been described, but there is a lack of studies that evaluate the structural changes of the nose and paranasal sinuses in ML using radiological methods. In this study, we aimed to assess the opacification of the paranasal sinuses in patients with treated ML and any anatomical changes in the face associated with ML using multidetector computed tomography scans (MDCT) of the sinuses. We compared the findings with a control group. Methodology/Principal Findings: We evaluated 54 patients with treated ML who underwent CT scans of the sinuses and compared them with a control group of 40 patients who underwent orbital CT scans. The degree of sinus disease was assessed according to the Lund-Mackay criteria. Forty of the 54 patients with a history of ML (74.1%) had a tomographic score compatible with chronic sinusitis (Lund-Mackay >= 4). CT scans in the leishmaniasis and control groups demonstrated significant differences in terms of facial structure alterations. Patients from the ML group showed more severe levels of partial opacification and pansinus mucosal thickening (42.6%) and a greater severity of total opacification. Patients from the ML group with a Lund-Mackay score >= 4 presented longer durations of disease before treatment and more severe presentations of the disease at diagnosis. Conclusion/Significance: CT scans of the sinuses of patients with ML presented several structural alterations, revealing a prominent destructive feature of the disease. The higher prevalence in this study of chronic rhinosinusitis observed in CT scans of patients with treated ML than in those of the control group suggests that ML can be considered a risk factor for chronic rhinosinusitis in this population (p<0.05).
  • article 4 Citação(ões) na Scopus
    Cerebrospinal fluid shunt infection caused by Corynebacterium sp: Case report and review
    (2014) MIURA, Flavio Key; ANDRADE, Almir Ferreira; RANDI, Bruno Azevedo; AMATO, Valdir Sabbaga; NICODEMO, Antonio Carlos
    Background: A 36-year-old immunocompetent woman with a posterior fossa arteriovenous malformation (PF-AVM) and hydrocephalus presented with low fever and mental confusion 4 days after ventriculoperitoneal shunting (VPS). Methods: Cerebrospinal fluid (CSF) and ventricular catheter tip cultures isolated Corynebacterium sp. Similar to previous cases in the literature, species determination was not possible. However, the antibiotic sensitivity profile of this isolate suggested Corynebacterium jeikeium. Conversion to external ventricular drainage (EVD) was done and intravenous vancomycin was administered for 21 days. Results and conclusions: The patient showed progressive improvement. Since the first CSF shunt infection caused by Corynebacterium sp., 16 other cases in the literatures have been reported. Additionally, this study reports the difficulties in recognizing CSF shunt infection caused by this agent and the possible clinical or laboratory patterns as observed in the literature.
  • article 31 Citação(ões) na Scopus
    Liposomal formulation of amphotericin B for the treatment of mucosal leishmaniasis in HIV-negative patients
    (2014) ROCIO, Carolina; AMATO, Valdir Sabbaga; CAMARGO, Raphael A.; TUON, Felipe F.; NICODEMO, Antonio Carlos
    Background: Studies assessing the efficacy of liposomal amphotericin B (LAB) in the treatment of patients with mucosal leishmaniasis (ML) are very scarce in the literature and an optimal dose regimen has not yet been defined. Methods: We performed a retrospective and descriptive analysis from records of 16 patients with ML treated with LAB. The mean daily dose of LAB was 2.5 mg/kg/day. Results: Healing of the lesion was observed in 14 (88%) of the 16 patients. The mean cumulative doses, excluding the two treatment failures, were 2265 mg and 33 mg/kg. Conclusion: Liposomal amphotericin B in the cumulative dose of 30 to 35 mg/kg was able to achieve 100% effectiveness.
  • article 9 Citação(ões) na Scopus
    USEFULNESS OF kDNA PCR IN THE DIAGNOSIS OF VISCERAL LEISHMANIASIS REACTIVATION IN CO-INFECTED PATIENTS
    (2013) NICODEMO, Antonio Carlos; AMATO, Valdir Sabbaga; TUON, Felipe Francisco; SOUZA, Regina Maia de; OKAY, Thelma Suely; ALMEIDA, Lucia Maria
    It is important to develop new methods for diagnosing relapses in the co-infection of visceral leishmaniasis (VL) and HIV to enable earlier detection using less invasive methods. We report a case of a co-infected patient who had relapses after VL treatment, where the qualitative kDNA PCR showed a good performance. The kDNA PCR seems to be a useful tool for diagnosing VL and may be a good marker for predicting VL relapses after treatment of co-infected patients with clinical symptoms of the disease.
  • article 7 Citação(ões) na Scopus
    Mucosal leishmaniasis mimicking T-cell lymphoma in a patient receiving monoclonal antibody against TNF alpha
    (2017) NICODEMO, Antonio Carlos; DUAILIBI, Daniel Fernandes; FERIANI, Diego; DUARTE, Maria Irma Seixas; AMATO, Valdir Sabbaga
  • article 8 Citação(ões) na Scopus
    Lipid nanoparticles for amphotericin delivery in the treatment of American tegumentary leishmaniasis
    (2020) SOUZA, Regina Maia de; MARANHAO, Raul Cavalcante; TAVARES, Elaine Rufo; FILIPPIN-MONTEIRO, Fabiola Branco; NICODEMO, Antonio Carlos; MORIKAWA, Aleksandra Tiemi; KANASHIRO, Edite Hatsumi Yamashiro; AMATO, Valdir Sabbaga
    Leishmaniasis occurs in the five continents and represents a serious public health challenge, but is still a neglected disease, and the current pharmacological weaponry is far from satisfactory. Triglyceride-rich nanoparticles mimicking chylomicrons (TGNP) behave metabolically like native chylomicrons when injected into the bloodstream. Previously we have shown that TGNP as vehicle to amphothericin B (AB) for treatment of fungi infection showed reduced renal toxicity and lower animal death rates compared to conventional AB. The aim of the current study was to test the tolerability and effectiveness of the TGNP-AB preparation in a murine model of Leishmania amazonensis infection. The in vitro assays determined the cytotoxicity of TGNP-AB, AB, and TGNP in macrophages and promastigote forms and the leishmanicidal activity in infected macrophages. The in vivo toxicity tests were performed in healthy mice with increasing doses of TGPN-AB and AB. Then, animals were treated with 2.5 mg/kg/day of AB, 17.5 mg/kg/day of TGNP-AB, or TGNP three times a week for 4 weeks. TGNP-AB formulation was less cytotoxic for macrophages than AB. TGNP-AB was more effective than AB against the promastigotes forms of the parasite and more effective in reducing the number of infected macrophages and the number of amastigotes forms per cell. TGNP-AB-treated animals showed lower hepatotoxicity. In addition, TGNP-AB group showed a marked reduction in lesion size on the paws and parasitic load. The TGNP-AB preparation attained excellent leishmanicidal activity with remarkable lower drug toxicity at very high doses that, due to the toxicity-buffering properties of the nanocarrier, become fully tolerable.
  • conferenceObject
    Visceral leishmaniasis reactivation diagnosed by molecular technique in blood sample
    (2012) BRAZ, L.; NICODEMO, A.; SOUZA, R.; SANTOS, N.; GODOY, N.; OKAY, T.; AMATO, V.
    Background: It is possible to perform the serological diagnosis of visceral leishmaniasis through k39 immunochromatographic test. However, usually in the co-infection visceral leishmaniasis with HIV k39 strip results are not conclusive. Then, investigation by microscopic examination of smear, culture medium NNN/BHI and PCR can be performed in bone marrow aspirates (gold standard) or blood sample. In this case report PCR in blood sample proved to be useful for monitoring reactivation of visceral leishmaniasis in a patient with HIV. Methods: In four different periods of a patient hospitalization with visceral leishmaniasis, samples of bone marrow aspirates and peripheral blood were examined. They were evaluated by microscopic examination of smear stained by Panóptico, culture medium NNN/BHI and PCR targeting the kDNA. Results: In four different periods of patient hospitalization the samples from bone marrow aspirates and blood sample presented amastigotes after smear microscopic examination. By PCR (kDNA) the samples from bone marrow aspirates and blood sample showed a 120-bp band on the electrophoresis gel. And promastigotes were found in the culture medium NNN/BHI from aspirated bone marrow only in the last hospitalization. Conclusion: Aspiration of bone marrow, the gold-standard diagnostic laboratory of visceral leishmaniasis, is known to be invasive and painful. However, it is possible to diagnose the disease through k39 immunochromatographic test. But usually in patients coinfected with HIV the k39 results are not conclusive. And the microscopic examination of smear is subjective and extremely time consuming. Our results of positive PCR (120 bp) in both bone marrow aspirates and in the blood sample demonstrated the importance of PCR in detection of visceral leishmaniasis reactivation. PCR results in blood samples suggest the possibility of replacing the PCR and even the smear examination in bone marrow aspirates to detect reactivation.
  • article 29 Citação(ões) na Scopus
    Short Report: Can We Use a Lower Dose of Liposomal Amphotericin B for the Treatment of Mucosal American Leishmaniasis?
    (2011) AMATO, Valdir S.; TUON, Felipe F.; CAMARGO, Raphael A.; SOUZA, Regina M.; SANTOS, Carolina R.; NICODEMO, Antonio C.
    Liposomal amphotericin B has been used as an alternative treatment of mucosal leishmaniasis, but the optimal dose is not established. We retrospectively reviewed the clinical outcome of eight patients with mucosal leishmaniasis treated with liposomal amphotericin B. The mean total dose was 35 mg/kg (range 24-50 mg/kg), which resulted in the healing of all the lesions in all patients and no recurrences were observed during the follow-up period (mean 25 months; range 7-40 months).
  • article 5 Citação(ões) na Scopus
    Are the severe injuries of cutaneous leishmaniasis caused by an exacerbated Th1 response?
    (2012) NICODEMO, A. C.; AMATO, V. S.; MIRANDA, A. M.; FLOETER-WINTER, L. M. F.; ZAMPIERI, R. A.; FERNADES, E. R.; DUARTE, M. I. S.
    American tegumentary leishmaniasis (ATL) is a disease whose clinical features are strongly related to the type of immune response it induces. Herein we report an atypical presentation of cutaneous leishmaniasis in a woman with a severe and extensive sore located in her leg, and we describe the differences between the usual local immune response in ATL and the local immune response in this patient. We observed an intense inflammatory response characterized by Th1 cells and cytokines with conspicuous expression of Toll-like receptor 3 (TLR-3). Few parasites were present, but there was an extensive tissue damage. We also discuss the immunological factors that could be related to the atypical presentation.